To use the word courtship makes the analogous activity involving employers sound rather stately and dignified. Which it isn't. Résumés get 20 seconds and minds are made up in the first three seconds of an interview.
It's more like speed dating.
Put really briefly, in a study of speed dating Marco Francesconi1 found, "Who you propose a date to is largely a function of who happens to be sitting in front of you." Women who are slim, tall professionals get snapped up first. Otherwise it is whoever is there that get's offered a date.
So how does this apply to employment, you ask?
It actually ties in with another study that shows that business sales people who get to sales leads first get the business. And being first in the Internet age means being within the first five minutes rather than the first ten. (No exaggeration.) In the case of employment it means that the job seeker must know about all of the jobs available, and knowing about them early, before prospective dates go away.
I would even say it means that networking is nice, provided that it does not obviate the use of other sources. The job seeker needs to be available to date lots of employers.
1How much of who you choose to date is determined by your preferences vs "market conditions"?